Assessment of Hg accumulation in fish and scalp hair in fishing communities along river Swat, Pakistan.

Mercury (Hg) bioaccumulation in fish poses severe threats to the food safety and human health. This study was conducted to assess Hg bioaccumulation in fish (n = 24) and scalp hair (n = 77) of the fishing communities at up- and downstream of the river Swat, Pakistan. The mean Hg concentration in upstream fish Salmo trutta fario (Brown trout) and Schizothorax plagiostomus (Swati fish) species was 34.7±18 µg kg-1 and 29.4±15 µg kg-1, respectively. The mean Hg concentration in downstream Swati fish, Crossocheilus diplochilus (Spena deqa), and Garra gotyla (Tora deqa) was 65±21 µg kg-1, 123±33 µg kg-1, and 326±53 µg Kg-1, respectively. The mean Hg concentration in scalp hair of the up- and downstream fishing communities was 658±125 µg kg-1 and 3969±791 µg kg-1, respectively. Independent T-test showed significant difference (p < 0.001) in the mean Hg concentration in scalp hair of the up- and downstream communities. The most prevalent health problems found in the fishing community were muscle pain, headache, visual impairment, arterial blood pressure, anemia, and kidney dysfunction. Multiple linear regression indicated that daily and weekly consumption of the fish significantly increase Hg accumulation in human scalp hair. Regular consumption of fruits and cruciferous and leafy vegetables were found to reduce Hg toxicity in the population. Further studies are recommended to identify the sources of Hg and welfare impact of fish contamination on the fishing community of river Swat.

Occupational Exposure Assessment of Major and Trace Elements in Human Scalp Hair Among a Group of Eritrean Workers.

The aim of the study was to evaluate occupational exposure to 40 elements among a group of Eritrean adults employed at the Medeber metal market by analysing human scalp hair samples and by investigating the role of some predictors (gender, age, and body mass index-BMI) on their levels. Scalp hair samples were collected from 60 subjects (32 subjects working at the Medeber metal market and 28 subjects not working at Medeber and not employed in other industrial or artisanal activities) and were analysed through inductively coupled plasma mass spectrometry to determine the contents of 40 major and trace elements. Information on participants was collected via questionnaire. Significant differences were found in the hair levels of certain elements between subjects working at the Medeber metal market and subjects not exposed. In particular, working at the Medeber metal market increased hair levels of Be, B, Cu, Zn, Mo, Cd, Sb, Tl, Pb, and Fe from 25 to 100%, while reduced Na, K, and Rb levels from 30 to 50%. With multivariate adjustment for age, gender, and BMI, the results confirm that working at Medeber significantly increased the hair levels of Cu, Zn, Sb, Pb, and Fe. This finding reveals the need for more accurate and routine biomonitoring surveys and the necessity of health promotion campaigns both for local decision-makers and workers to increase health promotion and safety in this workplace.

A population assessment of mercury exposure from two cities of Pakistan with respect to freshwater and marine fish consumption.

In this study, we aimed to estimate the level of mercury (Hg) in scalp hair samples of human subjects and its association with consumption of sea- and freshwater fish species. The scalp hairs were collected from both genders (male and female) aged between 15 and 50 years (n = 200), living in coastal areas of Karachi, who mostly consumed sea fish species, referred to as exposed subjects. For comparison purposes, scalp hair samples of both genders (n = 160) were collected from the inhabitants of Karachi and Hyderabad cities who consumed freshwater fish species termed as referent subjects. The frequently consumed fresh and marine fish species were also collected. The level of Hg was determined in fish and scalp hair samples by cold vapor atomic absorption spectrometry, prior to ultrasonic-assisted acid digestion in a mixture of nitric acid and hydrogen peroxide. The validity of methodology was checked by certified reference material (CRM) BCR 397 (human hair) and DORM-2. The concentrations of Hg in sea- and freshwater fish were found in the range of 1.47-2.09 and 0.402-0.676 µg/g, respectively. The exposed subjects had significantly elevated levels of Hg in scalp hair samples (1.8-4.3 µg/g) as compared to referent subjects (0.87-1.95 µg/g) (p < 0.001). A significant positive correlation was obtained between the concentration of Hg in hair and age of study population. Exposed and referent female subjects had higher levels of Hg in scalp hair than that in males of both study groups (p = 0.02-0.031).

Assessment of the antielastase activities in bronchoalveolar lavage fluid: effect of assay buffer ionic strength.

OBJECTIVE: To evaluate the effect of assay buffer ionic strength on assessment of the antielastase activities in bronchoalveolar lavage fluid. METHOD: An improved assay protocol in which elastase (in Tris-HCI buffer) is added to increasing volumes of test samples (made up to equal volume with phosphate-buffered saline) was used. RESULTS: The percent NE activity inhibited by BALF decreased with increasing NaCl concentration of the buffer. Inhibition of pancreatic elastase (PE) was not affected. One hundred percent inhibition of NE by pure AAT and SLPI standards occurred at molar ratios of 0.91 +/- 0.03 for AAT-to-NE and 0.83 +/- 0.02 for SLPI-to-NE when assayed in buffer with < or = 0.15 mol NaCl/L, compared to ratios of 0.99 +/- 0.02 and 1.06 +/- 0.02, respectively, for assays in buffers with 0.50-1.00 mol NaCl/L (p < 0.05 for AAT-to-NE; p < 0.02 for SLPI-to-NE). The AAT-to-PE molar ratio at 100% inhibition of PE was not affected. Assays in buffer with < or = 0.15 mol NaCl/L indicated that 86.9 +/- 4.1% of AAT and 100.9 +/- 4.9% of SLPI in BALF were active against NE, while assays in buffer with 0.50-1.00 mol NaCl/L showed that 84.4 +/- 3.5% of AAT and 81.6 +/- 5.9% of SLPI present were active. AAT inhibited NE and PE equally only in buffer with 0.50-1.00 mol NaCl/L. CONCLUSIONS: The results of assays of BALF antielastase activities depend on the assay buffer NaCl concentration, which may account for the conflicting reports in the literature. The buffer with 0.50-1.00 mol NaCl/L appear to be optimal for valid quantitation of anti-NE activities in BALF.